During the three-hour meeting at South Block, the prime minister evaluated the security preparedness across the country and the troop response, they said.

The exercise came a day after India put its armed forces on high alert.

"The army, navy and air force, which were already on alert, were Friday put on high alert," a defence source said on condition of anonymity.

On Thursday, Defence Minister Antony had reviewed the security environment along the land and maritime borders in a meeting with the three service chiefs and the defence secretary.

"The services were asked to put a suitable mechanism in place to ensure proper analysis and follow-up of all relevant inputs. The security of vital coastal and offshore assets was discussed with a view to ensuring that these remained fully secured," defence spokesman Sitanshu Kar had then said.

Antony had Tuesday told reporters: "I cannot say what course of action we will take, but unless Pakistan shows sincerity in whatever they are saying through their actions, one thing is very sure - that there is no question of things as usual."

Ten terrorists who struck Mumbai Nov 26 and left over 170 people, including 26 foreigners, dead had come from Pakistan, India has maintained. While Pakistan has offered all help in investigation, it has sought evidence that the attackers were from its soil.